Naruto would probably be really angry at first. He's a free - spirited person who doesn't like being forced into things. So he'd likely try to fight back right away, yelling at Sasuke about what he's doing.
Sakura would be heartbroken. She'd likely spend hours upon hours by Naruto's side, trying to jog his memory with stories of their adventures together. She might even get a bit overbearing in her attempts. Sasuke, who has his own complex relationship with Naruto, would be conflicted. He'd see Naruto's forgetfulness as a sign of weakness at first but then realize the importance of their bond. Kakashi, being the experienced leader, would start by observing Naruto carefully to see exactly how much he has forgotten and then start a systematic process of helping him remember.
The ninja community's reaction would be quite mixed. Some, like Naruto's close friends such as Shikamaru and Kakashi, would be supportive. They would likely offer their protection and assistance to Naruto during his pregnancy. However, there would also be those who are more traditional and might view Naruto's pregnancy as a weakness or something that goes against the norms of the ninja world. They could try to isolate Naruto or even oppose Sasuke's relationship with him because of it.
Sasuke would likely be devastated. Despite their past differences, Naruto was his rival and in a way, his closest friend. He might go into a deep state of regret and isolation. Sakura would be heart - broken. She loved Naruto, and his death would be a huge blow to her. She might become more withdrawn and focus all her energy on her medical ninjutsu. Kakashi would be filled with a sense of failure. He was Naruto's teacher, and he would feel responsible for not being able to protect him.
Sasuke might initially be indifferent on the surface, but deep down he would feel a sense of loss. He has always had a rivalry with Naruto, and Naruto's departure would mean an end to that dynamic. Sakura would be devastated. She has grown to care about Naruto as a friend and teammate, and his leaving would leave a big hole in the team.
On the other hand, Sasuke could be worried. He may think that Naruto is in some kind of trouble or danger. Given their history and the care they have for each other in the SasuNaru dynamic, Sasuke's concern could lead him to be more protective. He might start investigating the situation on his own to figure out why Naruto is hiding his face and ensure his safety.
Well, Sasuke might initially be a bit shocked but then he'd try to hide his concern. Sakura would be very empathetic and might immediately want to do something to help Naruto. Kakashi, being the experienced one, would take a more calm and strategic approach to deal with Naruto's situation and protect him from further abuse.
They would be shocked at first. Minato would be filled with pride and joy seeing his son all grown up. Kakashi would respect Naruto's strength. Obito might be a bit envious of Naruto's popularity but also admire his spirit. Rin would be very friendly towards Naruto.
Sasuke might also be angry. Angry at the situation, angry at whoever or whatever caused Naruto's amnesia. His anger could fuel his determination to find a cure. He would push himself and Naruto harder in training, hoping that it would jog Naruto's memory, all while trying to hide his true feelings of worry and fear for Naruto's well - being.
He could feel a sense of guilt. Sasuke might think that his actions or their relationship issues pushed Naruto to leave. He may then set out to find Naruto, not only to bring him back but also to resolve their long - standing issues. For example, if there were unspoken words or unresolved fights between them, Sasuke would see this as an opportunity to set things right.